Radial velocity measurements and orbit determination of eight single-lined spectroscopic binary systems

TL;DR

This study presents new radial velocity measurements for eight single-lined spectroscopic binaries, refining their orbital parameters and providing updated solutions, including a notably longer and more eccentric orbit for phi Dra.

Contribution

The paper provides the first set of radial velocity measurements for these binaries and improves their orbital solutions, especially for phi Dra, using data from the FLECHAS spectrograph.

Findings

Constrained orbital solutions for seven binaries.

Redetermined orbit of phi Dra with longer period and higher eccentricity.

Collected 391 radial velocity measurements over 1.6 years.

Abstract

Since early 2015 a new radial velocity monitoring campaign is going on at the University Observatory Jena. The aim of this project is to obtain current radial velocity measurements of selected single-lined spectroscopic binary systems, to redetermine and/or constrain their orbital solutions. In this paper we characterize the properties of the target sample of the project, describe the spectroscopic observations, the data-reduction and analysis and present the first results of the project, taken with the fiber-linked astronomical spectrograph FLECHAS. We present 391 radial velocity measurements of eight spectroscopic binaries, which were taken within an epoch difference of 1.6 years. These radial velocities were used to determine the spectroscopic orbital elements of the observed binary systems, which exhibit orbital periods in the range between nearly one up to several dozens of days. We could constrain the orbital solutions of seven of these binary systems, and redetermine the orbital solution of phi Dra, whose orbit exhibits >4 times longer orbital period and is more eccentric than given in the 9th Catalogue of Spectroscopic Binary Orbits.